Sessional_Paper_1903 — Page 611

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The most interesting experiment and the crucial test as to the causal relation- ship of the bacillus to the disease is given in detail under the heading "leifer Calf E." From this experiment alone, there can exist no further doubt as to the bacillary nature of the disease which we have had the opportunity of investigating, The bacillus which we regard as the exciting agent of this pestilent disease fulfils therefore to the full extent KocH's postulates:-

(1.) It can be isolated from every case of the disease.

(2.) Pure cultures of the bacillus give rise to a similar septicemic and

hæmorrhagic disease in many of the lower animals.

(3.) Pure cultures of the micro-organisms give rise to the disease in

characteristic form in bullocks of the same species.

(4.) And from all animals experimented with, including oxen, the

bacillus can again be isolated in pure cultures.

BULLOCK "A".

The animal was perfectly healthy previous to experiment. Its temperature averaged 100° F. to 101° F. for two days previously.

On the 3rd day it was inoculated subcutaneously into the upper third of the neck, just in front of the shoulder with 10 c.c. of fresh blood from Ox No. 145, obtained from the heart within a few minutes after death.

The disease in Ox No. 145 ran a typical course-vide P.M. No. 39.

As will be observed from the accompanying tenperature chart, a decided rise in temperature was obtained on the 4th day after inoculation. Up to the 7th day after inoculation the animal showed no symptoms of disease. Food and drink were taken as if in perfect health.

On the 8th day after inoculation the animal refused food, rumination was suspended, and generally speaking showed an appearence of ill-health.

On the 9th day, diarrhoea set in. The discharges presented the characteristic black fluid, and foetid condition found in animals which had contracted the disease under natural circumstances. Rapid emaciation and severe prostration accom- panied the onset of the diarrhoea,

On the 10th day, the animal was unable to rise, and lay with legs stretched out, and head and neck flat on the ground. Respirations became short, hurried and shallow, and painful grunts accompanied each expiratory effort.

The animal rapidly sank, and died on the morning of the 11th day after inoculation.